I read on the forum threads a lot of discussion about AF tuning lens relative to the D800 focusing issue. As an amateur, what is the best way to do this? Any and all suggestions are appreciated. Thanks in advance!

Focal works, it the most expensive I think. Focus Tune is very similar to Focal for less money. Plus if you have a Lens Align kit, Focus Tune works with it very well. And the Dot Tune method also works well. Especially for free!
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